Pumping unit



B. R. MCBATH, JR

PUMPING UNIT March 7, 1939.

2 Sheets-Shot 2 Filed April 7, 1957 HJYI2 BATHJR..

mmvToR v or inlet of the centrifugal pump I until .nally all Patented Mar. 7, 1939 UNITED STATES -PATENT oFFlcE PUMPING UNIT Bartley R. McBath, Jr., Verona, N. J., assignor to Worthington Pump and Machinery Corpotion, Harrison, N. J., a corporation of Vir- Application April 7, 1937, Serial No. 135,361

2 Claims. (01.103-113) it loses its suction, in contradistinction to a dev vice which will prevent a pump from losing its suction, and to provide pump priming means of this type'which is relatively simple in construction and requires no delicate adjustment.

More specically the present invention comprises a pumping unit embodying an automatic device responsive to pressure developed on the discharge side of a centrifugal pump for controlling operation and/or unloading of an auxiliary air removal element for priming the centrifugal Pump-- 4 With these and otherobjects inV view, as` may appearfrom the accompanying speciiication, the invention consists of various -features of ccnstruction and combination of parts, which will be ilrst described inconnection with the accompanying drawings, showing a pumping unit of the preferred form embodying the invention, and the featuresforming the invention will be specifically pointed out in the claims.

In the drawings:

Figure 1 is a side elevation of pumping unit.

Figure 2 is an end elevation of the pumping unit.

Figure 3 is a diagrammatic view partly in section of the pumping unit.

Figure 4 is a .detailsection taken on the line 4-4 of Figure 1.

Referring-more particularly to the drawings, the improved pumping unit comprises a centrifugal pump I of any approved type, which is driven by a motor 2. The motor 2 also operates the air removal element or pump 3 which is an air removal pump of the water piston type, which is well known in the art. The air removal pump 3 is provided for withdrawing air from the centrifugal pump I to prime the centrifugal pump and permit of its operation. A pipe 4 is connected to the suction 5 of the centrifugal pump I and it is also connected to the suction of the air removal or vacum pump 3 through suitable couplings 5' and 6 so that when the motor 2 is started, the air removal pump 3 exhausts the suction system of the air is removed from the pump I- and water drawn into the pump primes it and it builds up its desired pressure. The discharge pressure of the centrifugal pump I is, when the pump isprimed,

the Uimproved transmitted through the pipe 1 to a pressure operated unloading valve 8. The pressure operated 'unloading valve 8 is of approved type, and the one vshown in the drawings is manufactured by the Fisher Governor Company, and while this particular type of pressure operated valve is desirable, it is to be understood that any suitable type of valve operated by pressure may be substituted for the particular type of valve shown in the drawings without departing from the spirit of the present invention.

atmosphere through the valve structure 8, the

pipe II land T coupling 6, thus permitting the pump 3 to operate unloaded. At this time atmospheric pressure will exhaust throughout the pipe 4 up to the check valve I2 lwhich is mounted therein, and by virtue of the fact that the pres- ,jsure on the suction side of the pump is less than atmosphere, the check valve I2 will close and v prevent the atmospheric-air from passing back into the pump I. The check valve I2 will remain closed as long as the pump I holds its prime, but should it for any reason lose its prime, the pressure through the pipe .'I will fall and the pressure operated valve 8 will close, cutting off` communication between the suction of the air removal pump 3 and atmosphere and opening the y suction of the air removal pump 3 to the suction 5 of the pump I. The suction pressure of the air removal pump 3 will open the check valve I2 and the pump 3 will then continue' to draw air and gases from the centrifugal pump I until this pump again picks up its prime.

The air removal pump 3 is, as previously stated, preferably of the type Lwhich utilizes a liquid piston in its operation, and for the purpose of providing a small quantity of liquid at all times, to seal or provide the necessary liquid piston for the pump 3, a bypass pipe I4 is provided which is conn'ected to the pipe I and consequently to the discharge of the centrifugal pump I, and to the coupling 5, which in turn is connected to the suction'of the air removal pump 3. A restricted orice shown at I5 is provided in the connectionbetween the bypass I4 and the suction I 6 of the air removal pump 3 so as to limit the quantity of liquid delivered to the air removal pump 3i-to a quantity whichlcan be readily handled by the pump 3 and discharged by it through its discharge I1, so as to prevent liquid from backing up in the pipe 4.

casacca A check valve 20 is placed in the pipe 'I between the pumps i and 3 and prevents the air removal pump 3 from drawing air through the discharge of the centrifugal pump l.

Strainers I8 and i9 are shown in the pipes d and 1, but they form no part of the present nvention. l

lFrom the foregoing description taken in connection with the accompanying drawings, it will be noted that in the present pumping unit the priming action of the air removal pump 3 is pressure controlled, and it is opened to atmosphere, for idle running by the discharge pressure of the centrifugal pump in contradistinction to the usual practice of controlling the operation of the air removal pump by the level of liquid pumped in a float chamber, and that with the present pressure control of the air removal pump, the relatively delicate adjustments necessary forfioat control of the air removal pump are eliminated, and also any liability of uttering of the control mechanism due to variances in liquidl level in a oat chamber is eliminated.

It will be understood that the invention is not to be limited to the specic construction or arrangement of parts shown but that they may be widely modied within the invention deiined by the claims.

erated diaphragm for actuating said valve, a pipe connected to the discharge of said centrifugal pump and said diaphragm whereby the diaphragm will be acted upon to open the valve and open the suction of the air removal pump to atmosphere when the discharge pressure of the centrifugal pump reaches a predetermined degree, a connection from said pipe to said conduit outwardly of the connection between said valve and the suction of said air removal pump for supplying make-up liquid, to the air removal pump, and a restricted orifice-at the connection ofsaid pipe and conduit.

2. In a pumping unit, in combination, a centrifugal pump, an auxiliary air removal pump, a conduit connecting the suctions of said pumps, a valve connected 'to the-suction of said air removal pump and to atmosphere, a pressure op- V`erated diaphragm for actuating said valve, a pipe connected to the discharge of said centrifugal pump and said diaphragm whereby the diaphragm will be acted upon to open the valve and open the suction of the air removal pumpto atmosphere when the discharge pressure of the centrifugal pump reaches a predetermined degree, a. connection from said pipe to said conduit outwardly of the connection between said valve and the suction of said air removal pump for supplying make-up liquid to the air removal pump, a restricted orice at the connection of said pipe and conduit, and non-return check valves in said pipe and conduit.

BABTLEY R. MCBATH, JR. 

